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Scaling in JavaFX and ScrollPanes

I am trying to work with scaling transform in JavaFX, but could not completely wrap it around. Basically, I have a panel containing a complex graph and would like to scale it. The scaling part itself works fine, however, the closing scroll panel will not adapt to the schedule.

For simplicity, I will post a short example in which my chart is replaced by a label:

public class TestApp extends Application {
    @Override public void start(final Stage stage) throws Exception {
        final Label label = new Label("Hello World");
        label.getTransforms().setAll(new Scale(0.5, 0.5));

        label.setStyle("-fx-background-color:blue");
        label.setFont(new Font(200));

        final ScrollPane scrollPane = new ScrollPane();
        scrollPane.setContent(label);

        stage.setScene(new Scene(scrollPane));
        stage.setWidth(200);
        stage.setHeight(100);
        stage.show();
    }

    public static void main(String[] args) {
        Application.launch(args);
    }
}

The shortcut will scale correctly, but the scrollbar cover panels will still contain the original size component.

I have tried so far:

  • Game labeled min and pref size
  • packing labels within a group (no scrollbars appear at all)
  • scaling of the enclosing group, not labels

? , ScrollPane ?

.

+5
2

ScrollPane scrollpane , JavaFX.

, JavaFX, , , , , (, node, ScrollPane).

(ScrollBars node , ), :

// create a container for the viewable node.
final StackPane nodeContainer = new StackPane();
nodeContainer.getChildren().add(node);

// place the container in the scrollpane and adjust the pane viewports as required.
final ScrollPane scrollPane = new ScrollPane();
scrollPane.setContent(nodeContainer);
scrollPane.viewportBoundsProperty().addListener(
  new ChangeListener<Bounds>() {
  @Override public void changed(ObservableValue<? extends Bounds> observableValue, Bounds oldBounds, Bounds newBounds) {
    nodeContainer.setPrefSize(
      Math.max(node.getBoundsInParent().getMaxX(), newBounds.getWidth()),
      Math.max(node.getBoundsInParent().getMaxY(), newBounds.getHeight())
    );
  }
});

...

// adjust the view layout based on the node scalefactor.
final ToggleButton scale = new ToggleButton("Scale");
scale.setOnAction(new EventHandler<ActionEvent>() {
  @Override public void handle(ActionEvent actionEvent) {
    if (scale.isSelected()) {
      node.setScaleX(3); node.setScaleY(3);
    } else {
      node.setScaleX(1); node.setScaleY(1);
    }
    // runlater as we want to size the container after a layout pass has been performed on the scaled node.
    Platform.runLater(new Runnable() { 
      @Override public void run() {
        nodeContainer.setPrefSize(
          Math.max(nodeContainer.getBoundsInParent().getMaxX(), scrollPane.getViewportBounds().getWidth()),
          Math.max(nodeContainer.getBoundsInParent().getMaxY(), scrollPane.getViewportBounds().getHeight())
        );
      }
    });
  }
});
+3

ScrollPane , ScrollPane , .

ScrollPane layout calculations are based on the layoutBounds rather than the
boundsInParent (visual bounds) of the scroll node. If an application wants the
scrolling to be based on the visual bounds of the node (for scaled content etc.),
they need to wrap the scroll node in a Group.
+8

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